12522221 has 2 divisors, whose sum is σ = 12522222. Its totient is φ = 12522220.

The previous prime is 12522193. The next prime is 12522227. The reversal of 12522221 is 12222521.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 12145225 + 376996 = 3485^2 + 614^2 .

It is an emirp because it is prime and its reverse (12222521) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 12522221 - 2⁶ = 12522157 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 12522221.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (12522227) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6261110 + 6261111.

It is an arithmetic number, because the mean of its divisors is an integer number (6261111).

Almost surely, 2^12522221 is an apocalyptic number.

It is an amenable number.

12522221 is a deficient number, since it is larger than the sum of its proper divisors (1).

12522221 is an equidigital number, since it uses as much as digits as its factorization.

12522221 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 160, while the sum is 17.

The square root of 12522221 is about 3538.6750345292. The cubic root of 12522221 is about 232.2168812655.

Adding to 12522221 its reverse (12222521), we get a palindrome (24744742).

The spelling of 12522221 in words is "twelve million, five hundred twenty-two thousand, two hundred twenty-one".